摘要
我国已发现十几处科马提岩,但绝大部分是科马提质玄武岩,而不是河南南阳独山发现的橄榄质科马提岩。独山科马提岩中的矿物,95％是橄榄石(现大部分已蚀变为蛇纹石、滑石和磁铁矿)、少量为单斜辉石(现大部分已蚀变为蛇纹石和滑石)和铬铁矿等。岩石县各种形态的鬣刺结构,鬣刺最长可达30cm,岩石含SiO_2 32.00％～40.00％,MgO 30.00％～37.88％,TiO_20.02％～0.10％,K_2O 0.00％～0.02％,CaO/Al_2O_3大部分小于1。在岩石化学图中,化学分析数据全部落在橄榄质科马提岩区。
Komatiite has been found within more than ten places in China, mostof which belong to komatiitic basalts rather than olivine komatiites disco-vered in Dusan, Nanyang, Henan. Minerals in komatiite in Dusan are com-posed of olivine in 95% amount and in less amount, clinopyroxene, chro-mite and so on. Rocks show spinifex textures of various shapes. The ma-ximum size of spinifex grain is up to 30 cm in length. The characteristics ofpetrochemistry of Dusan komatiite are as follows: SiO_2-32.00%～40.00%,MgO-30.00%～37. 88%, TiO_2-0. 02%～0. 10%, K_2O--0. 00%～0. 02%, CaO/Al_2O_3-mostly less than 1. All data fall into the olivine komatiite areain the petrochemical diagram.
